Formation of Low-Molecular-Weight Dissolved Organic Nitrogen in Predenitrification Biological Nutrient Removal Systems and Its Impact on Eutrophication in Coastal Waters

Eom, Heonseop; Borgatti, Douglas; Paerl, Hans W.; Park, Chul

doi:10.1021/acs.est.6b06576

Cited by 81 publications

(59 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, two additional samples collected near sewage treatment plants upstream at Guangzhou and downstream at Macau showed depleted δ 15 DON values (−2.5‰ and −0.9‰). Second, nitrifying bacteria are known to produce soluble microbial products during the biological processing of domestic sewage, contributing large amounts of newly produced DON to the DON pool in the effluent (Eom et al, ; Ni et al, ), which would therefore add isotopically depleted DON to the estuary. In fact, recent work employing stable and radiogenic isotopic techniques has also shown that the final treated effluents are depleted in δ 13 DOC (−29‰ to −27.9‰) relative to raw sewage (−22.7‰ to −23.6‰), which was attributed to the new sources of OC added during the treatment processes (Bridgeman et al, ).…”

Section: Discussionmentioning

confidence: 99%

The Sources and Transformations of Dissolved Organic Matter in the Pearl River Estuary, China, as Revealed by Stable Isotopes

Guo

Wei

et al. 2018

JGR Oceans

View full text Add to dashboard Cite

To investigate the sources and transformation processes of bulk marine dissolved organic matter (DOM), seasonally collected water samples from the Pearl River Estuary (PRE), south China, were analyzed for concentration and stable isotopic ratios (δ 13 C and δ 15 N) of DOM. The δ 13 C values clearly indicated a shift of dissolved organic carbon (DOC) sources from terrigenous material in the river to predominantly plankton in the lower estuary. The distribution of δ 13 C during the estuarine mixing, in combination with the notable deviation of DOC concentration, provided strong evidence for a substantial DOC removal in the salinity range of 5 to 22. In contrast to δ 13 C, the δ 15 N of DOM exhibits a strong seasonality, implying a clear decoupling of estuarine DOC and dissolved organic nitrogen (DON) dynamics. During dry periods with low river discharge, sewage-derived DON contributed significantly to the riverine loading. While freshwater-saltwater mixing is important in regulating the distribution of DON, the distribution of δ 15 N along the salinity gradient provided strong evidence for active sediment-water interaction and adsorption/desorption processes at the middle to high salinities. During wet periods, severe soil loss and erosion, and/or in situ biological production, adsorption onto suspended particles dominate the riverine DON fluxes, whereas the DON dynamics might be governed by different biogeochemical processes between spring and summer, as reflected by distinct δ 15 DON patterns in the estuarine zone. In spring, highly degraded DON originating from soil experienced little further biological alternation during estuarine mixing, whereas there was a tight coupling of DON production and consumption in summer.Plain Language Summary Isotopic evidence shows a clear decoupling of DOC and DON dynamics in the Pearl River Estuary, south China. DOC undergoes substantial removal in the salinity range of 5 to 22. Estuarine DON dynamics are influenced by both biotic and abiotic processes.

show abstract

Section: Discussionmentioning

confidence: 99%

The Sources and Transformations of Dissolved Organic Matter in the Pearl River Estuary, China, as Revealed by Stable Isotopes

Guo

Wei

et al. 2018

JGR Oceans

View full text Add to dashboard Cite

show abstract

“…Since dissolved inorganic nitrogen (DIN) can be efficiently removed in wastewater treatment plants (WWTPs), especially those with biological nutrient removal processes, dissolved organic nitrogen (DON) has become a non-negligible even major portion (25–95%) of residual nitrogen in the effluent. − In particular, microbe-derived DON (i.e., mDON) constitutes the major portion of effluent DON in the conventional activated sludge (AS) process . These mDON substances, such as amino acids and their derivates, are active precursors of nitrogenous disinfection byproducts .…”

Section: Introductionmentioning

confidence: 99%

“…These mDON substances, such as amino acids and their derivates, are active precursors of nitrogenous disinfection byproducts . More importantly, AS-derived mDON is highly bioavailable to facilitate phytoplankton growth but recalcitrant to degradation by AS-like communities . Hence, developing non-AS-based technologies for mDON control is practically meaningful to alleviate DON contamination, which could further reduce nitrogen discharges and ultimately mitigate eutrophication in aquatic environments.…”

Section: Introductionmentioning

confidence: 99%

Algae Biofilm Reduces Microbe-Derived Dissolved Organic Nitrogen Discharges: Performance and Mechanisms

Lin

Wang

et al. 2021

Environ. Sci. Technol.

View full text Add to dashboard Cite

Microbe-derived dissolved organic nitrogen (mDON) can readily induce harmful phytoplankton blooms, and thus, restricting its discharges is necessary. Recently, algae biofilm (AB) has attracted increasing interest for its advantages in nutrient recovery. However, its features in mDON control remain unexplored. Herein, AB's mDON formation and utilization performance, molecular characteristics, and metabolic traits have been investigated, with activated sludge (AS) as the benchmark for comparisons. Comparatively, AB reduced mDON formation by 83% when fed with DON-free wastewater. When fed with AS's effluent, it consumed at least 72% of the exogenous mDON and notably reduced the amount of protein/amino sugar-like compounds. Irrespective of the influent, AB ultimately produced more various unsaturated hydrocarbon and lignin analogues. Redundancy and network analysis highlighted the algal−bacterial synergistic effects exemplified by cross-feeding in reducing mDON concentrations and shaping mDON pools. Moreover, metagenomics-based metabolic reconstruction revealed that cyanobacteria Limnothrix and Kamptonema spp. facilitated mDON uptake, ammonification, and recycling, which supplied the extensive nitrogen assimilatory demand for amino acids, vitamins, and cofactors biosynthesis, and therefore promoted mDON scavenging. Our findings demonstrate that regardless of the secondary or tertiary process, cyanobacteria-dominated AB is promising to minimize bioavailable mDON discharges, which has implications for future eutrophication control.

show abstract

“…Scholars have investigated the removal of dissolved inorganic nitrogen (DIN) using both processes successfully, but very little attention is paid to the removal of dissolved organic nitrogen (DON). Excessive release of DON into the environment can have negative effects; for example, as a nitrogen‐containing nutrient, DON can facilitate the growth of microorganisms (Eom et al, 2017) and meet the needs of harmful algal species such as Karenia brevis , resulting in an algal bloom (Rabalais, 2002; Sinclair et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Molecular characterization of dissolved organic nitrogen during anoxic/oxic and anammox processes using ESI FT–ICR MS

Zhang

Zheng

Wang

et al. 2021

Water Environment Research

View full text Add to dashboard Cite

Dissolved organic nitrogen (DON) is a component of wastewater with a negative influence on the environment. The removal of DON is conducted through the anoxic/oxic (A/O) and anammox processes. However, the mechanisms and chemical preferences in the removal of DON compounds have not been understood and compared so far. This study, for the first time, comparatively investigated the molecular‐level characteristics of DON during both processes by using FT–ICR MS (Fourier transform ion cyclotron resonance mass spectrometry). The results indicated that the number of DON formulas increased from 1844 to 1935 during A/O process, and from 2784 to 3242 during anammox process, highlighting the increase in complexity of DON after undergoing both processes. DON with high saturation and aliphatic structures was removed by A/O process, whereas highly unsaturated and aromatic structures were removed by anammox process. For DON without S atom, Lignin‐like and tannin‐like ones were resistant to both processes and protein‐like and condensed aromatic structures were resistant to anammox process. The complementarity of these two processes provided a sequential combination with sufficient theoretical support to improve DON removal efficiency. Practitioner points Molecular components of dissolved organic nitrogen characterized by ESI FT–ICR MS. DON removal preferences of A/O and anammox processes evaluated. A/O and anammox processes are effective to remove aliphatic and aromatic DON, respectively. Complementarity in removal preferences of A/O and anammox processes can remove recalcitrant DON of each other. Sequential A/O and anammox processes can improve DON removal.

show abstract

Formation of Low-Molecular-Weight Dissolved Organic Nitrogen in Predenitrification Biological Nutrient Removal Systems and Its Impact on Eutrophication in Coastal Waters

Cited by 81 publications

References 40 publications

The Sources and Transformations of Dissolved Organic Matter in the Pearl River Estuary, China, as Revealed by Stable Isotopes

The Sources and Transformations of Dissolved Organic Matter in the Pearl River Estuary, China, as Revealed by Stable Isotopes

Algae Biofilm Reduces Microbe-Derived Dissolved Organic Nitrogen Discharges: Performance and Mechanisms

Molecular characterization of dissolved organic nitrogen during anoxic/oxic and anammox processes using ESI FT–ICR MS

Contact Info

Product

Resources

About